The restoration of decayed dental structures including caries, decayed dentin or decayed enamel, is often accomplished by the sequential application of a dental adhesive and then a dental material (e.g., a restorative material) to the relevant dental structures. Similarly, adhesives are used in the bonding of orthodontic appliances (generally also utilizing an orthodontic adhesive) to a dental structure. Often various pretreatment processes are used to promote the bonding of adhesives to dentin or enamel, for example. Typically, such pretreatment steps include etching using, for example, inorganic or organic acids, followed by priming to improve the bonding between the tooth structure and the overlying adhesive.
Whether for application of dental restoratives (e.g., composites, fillings, sealants, inlays, onlays, crowns, bridges, etc.) or orthodontic appliances to a tooth structure, the etchants, primers, and adhesives are typically applied in a step-wise fashion. Often between such steps, one or more rinsing and drying steps are used. As a result, dental restoration and the application of orthodontic appliances typically involve multi-step procedures.
To simplify conventional restorative and/or orthodontic procedures, for example, it would be desirable to provide a single composition that accomplishes both etching and priming. Thus, there is a need for a self-etching primer, particularly a self-etching dental primer, for improved bonding of an adhesive (e.g., a dental adhesive) to a substrate surface (e.g., dental structure, such as dentin, enamel, bone, or other hard tissue) and that could eliminate the conventional post-etching rinsing and drying steps. Furthermore, there is still a need for new compositions that can serve as self-etching adhesives, i.e., a single-composition adhesive with priming and etching properties that can be applied in a single pretreatment step. Preferred embodiments of the present invention meet some of these needs.